Spectral analysis has emerged as an efficient and accurate tool for quantitative analysis. For example, given a physical sample of unknown composition, infrared spectral analysis can be used to determine the amount of a particular substance present in the sample.
Typically, a test process is performed on the sample, and an infrared spectrum is produced. The spectrum can then be analyzed via various mathematical techniques to generate output values indicating masses of various substances in the sample. The substances are sometimes called “analytes.”
Some analytes are of particular interest because they are known to cause or aggravate disease. For example, exposure to quartz (i.e., crystalline silica) has long been recognized as a cause or aggravating factor for a variety of diseases, such as silicosis or coal worker's pneumoconiosis. Further, quartz is suspected of causing lung cancer. For the safety of persons working in an environment in which quartz is likely present (e.g., a mine), it is often desired to measure the airborne concentrations of quartz dust in the environment. Such measurement can be accomplished by analyzing the amount of quartz on filters that have been exposed to the environment (e.g., air sampling dust filters worn by the workers).
Thus, there are a number of laboratories across the world performing quantitative analyses of dust samples for quartz content. Infrared spectroscopy can be used to determine quartz mass. A laboratory may perform analyses on tens of thousands of samples per year. Such large scale analysis is expensive and may require many highly-skilled personnel. Due to misunderstandings relating to proper spectroscopy analysis procedure, unskilled personnel can easily introduce error into the process, and even skilled personnel can inadvertently introduce human error into the process.
Further, different laboratories may apply different techniques or use different equipment for performing quantitative analyses. As a result, it is difficult for laboratories to mutually share and implement a fully consistent method that determines the amount of quartz in samples and whether the amount present indicates risk to workers.